docs/apex/APEX-PCVS-Example.rst

   1 .. This work is licensed under a Creative Commons Attribution 4.0 International License.
   2 .. http://creativecommons.org/licenses/by/4.0
   3
   4 .. _apex-PCVSExample:
   5
   6 Policy-controlled Video Streaming (pcvs) with APEX
   7 **************************************************
   8
   9 .. contents::
  10     :depth: 3
  11
  12 Introduction
  13 ^^^^^^^^^^^^
  14
  15       .. container:: sectionbody
  16
  17            .. container:: paragraph
  18
  19               This module contains several demos for
  20               Policy-controlled Video Streaming (PCVS). Each demo
  21               defines a policy using AVRO and Javascript (or other
  22               scripting languages for the policy logic). To run the
  23               demo, a vanilla Ubuntu server with some extra software packages is required:
  24
  25                .. container:: ulist
  26
  27                   -  Mininet as network simulator
  28
  29                   -  Floodlight as SDN controller
  30
  31                   -  Kafka as messaging system
  32
  33                   -  Zookeeper for Kafka configuration
  34
  35                   -  APEX for policy control
  36
  37 Install Ubuntu Server and SW
  38 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  39
  40           .. container:: sect1
  41
  42             .. rubric:: Install Demo
  43                :name: install_demo
  44
  45             .. container:: sectionbody
  46
  47                .. container:: paragraph
  48
  49                   Requirements:
  50
  51                .. container:: ulist
  52
  53                   -  Ubuntu server: 1.4 GB
  54
  55                   -  Ubuntu with Xubuntu Desktop, git, Firefox: 2.3 GB
  56
  57                   -  Ubuntu with all, system updated: 3 GB
  58
  59                   -  With ZK, Kafka, VLC, Mininet, Floodlight, Python:
  60                      4.4 GB
  61
  62                   -  APEX Build (M2 and built): M2 ~ 2 GB, APEX ~3.5 GB
  63
  64                   -  APEX install (not build locally): ~ 300 MB
  65
  66                .. container:: paragraph
  67
  68                   On a Ubuntu OS (install a stable or LTS server first)
  69
  70                .. container:: listingblock
  71
  72                   .. container:: content
  73
  74                      ::
  75
  76                         # pre for Ubuntu, tools and X
  77                         sudo apt-get  -y install --no-install-recommends software-properties-common
  78                         sudo apt-get  -y install --no-install-recommends build-essential
  79                         sudo apt-get  -y install --no-install-recommends git
  80                         sudo aptitude -y install --no-install-recommends xubuntu-desktop
  81                         sudo apt-get  -y install --no-install-recommends firefox
  82
  83
  84                         # install Java
  85                         sudo add-apt-repository ppa:webupd8team/java
  86                         sudo apt-get update
  87                         sudo apt-get -y install --no-install-recommends oracle-java8-installer
  88                         java -version
  89
  90
  91                         # reboot system, run system update, then continue
  92
  93                         # if VBox additions are needed, install and reboot
  94                         sudo (cd /usr/local/share; wget https://www.virtualbox.org/download/testcase/VBoxGuestAdditions_5.2.7-120528.iso)
  95                         sudo mount /usr/local/share/VBoxGuestAdditions_5.2.7-120528.iso /media/cdrom
  96                         sudo (cd /media/cdrom;VBoxLinuxAdditions.run)
  97
  98
  99                         # update apt-get DB
 100                         sudo apt-get update
 101
 102                         # if APEX is build from source, install maven and rpm
 103                         sudo apt-get install maven rpm
 104
 105                         # install ZooKeeper
 106                         sudo apt-get install zookeeperd
 107
 108                         # install Kafka
 109                         (cd /tmp;wget http://ftp.heanet.ie/mirrors/www.apache.org/dist/kafka/1.0.0/kafka_2.12-1.0.0.tgz --show-progress)
 110                         sudo mkdir /opt/Kafka
 111                         sudo tar -xvf /tmp/kafka_2.12-1.0.0.tgz -C /opt/Kafka/
 112
 113                         # install mininet
 114                         cd /usr/local/src
 115                         sudo git clone https://github.com/mininet/mininet.git
 116                         (cd mininet;util/install.sh -a)
 117
 118                         # install floodlight, requires ant
 119                         sudo apt-get install ant
 120                         cd /usr/local/src
 121                         sudo wget --no-check-certificate https://github.com/floodlight/floodlight/archive/master.zip
 122                         sudo unzip master.zip
 123                         cd floodlight-master
 124                         sudo ant
 125                         sudo mkdir /var/lib/floodlight
 126                         sudo chmod 777 /var/lib/floodlight
 127
 128                         # install python pip
 129                         sudo apt-get install python-pip
 130
 131                         # install kafka-python (need newer version from github)
 132                         cd /usr/local/src
 133                         sudo git clone https://github.com/dpkp/kafka-python
 134                         sudo pip install ./kafka-python
 135
 136                         # install vlc
 137                         sudo apt-get install vlc
 138
 139                .. container:: paragraph
 140
 141                   Install APEX either from source or from a distribution
 142                   package. See the APEX documentation for details. We
 143                   assume that APEX is installed in
 144                   ``/opt/ericsson/apex/apex``
 145
 146                .. container:: paragraph
 147
 148                   Copy the LinkMonitor file to Kafka-Python
 149
 150                .. container:: listingblock
 151
 152                   .. container:: content
 153
 154                      ::
 155
 156                         sudo cp /opt/ericsson/apex/apex/examples/scripts/pcvs/vpnsla/LinkMonitor.py /usr/local/src/kafka-python
 157
 158                .. container:: paragraph
 159
 160                   Change the Logback configuration in APEX to logic
 161                   logging
 162
 163                .. container:: listingblock
 164
 165                   .. container:: content
 166
 167                      ::
 168
 169                         (cd /opt/ericsson/apex/apex/etc; sudo cp logback-logic.xml logback.xml)
 170
 171          .. container:: sect1
 172
 173             .. rubric:: Get the Demo Video
 174                :name: get_the_demo_video
 175
 176             .. container:: sectionbody
 177
 178                .. container:: ulist
 179
 180                   -  For all download options of the movie please visit
 181                      http://bbb3d.renderfarming.net/download.html
 182
 183                   -  For lower-res downloads and mirrors see
 184                      https://peach.blender.org/download
 185
 186                .. container:: listingblock
 187
 188                   .. container:: content
 189
 190                      ::
 191
 192                         sudo mkdir /usr/local/src/videos
 193
 194                .. container:: paragraph
 195
 196                   Standard 720p (recommended)
 197
 198                .. container:: listingblock
 199
 200                   .. container:: content
 201
 202                      ::
 203
 204                         (cd /usr/local/src/videos; sudo curl -o big_buck_bunny_480p_surround.avi http://download.blender.org/peach/bigbuckbunny_movies/big_buck_bunny_480p_surround-fix.avi)
 205
 206                .. container:: paragraph
 207
 208                   Full HD video
 209
 210                .. container:: listingblock
 211
 212                   .. container:: content
 213
 214                      ::
 215
 216                         (cd videos; sudo curl -o bbb_sunflower_1080p_60fps_normal.mp4 http://distribution.bbb3d.renderfarming.net/video/mp4/bbb_sunflower_1080p_60fps_normal.mp4)
 217
 218
 219
 220 VPN SLA Demo
 221 ^^^^^^^^^^^^^
 222
 223           .. container:: sect1
 224
 225             .. container:: sectionbody
 226
 227                .. container:: paragraph
 228
 229                   This demo uses a network with several central office
 230                   and core switches, over which two VPNs are run. A
 231                   customer ``A`` has two location ``A1`` and ``A2`` and
 232                   a VPN between them. A customer ``B`` has two location
 233                   ``B1`` and ``B2`` and a VPN between them.
 234
 235                .. container:: imageblock
 236
 237                   .. container:: content
 238
 239                      |VPN SLA Architecture|
 240
 241                .. container:: paragraph
 242
 243                   The architecture above shows the scenario. The
 244                   components are realized in this demo as follows:
 245
 246                .. container:: ulist
 247
 248                   -  *CEP / Analytics* - a simple Python script taking
 249                      events from Kafka and sending them to APEX
 250
 251                   -  *APEX / Policy* - the APEX engine running the VPA
 252                      SLA policy
 253
 254                   -  *Controller* - A vanilla Floodlight controller
 255                      taking events from the Link Monitor and configuring
 256                      Mininet
 257
 258                   -  *Network* - A network created using Mininet
 259
 260                .. container:: paragraph
 261
 262                   The demo requires to start some software (detailed
 263                   below). To show actual video streams, we use ``VLC``.
 264                   If you do not want to show video streams, but only the
 265                   policy, skip the ``VLC`` section.
 266
 267                .. container:: paragraph
 268
 269                   All shown scripts are available in a full APEX
 270                   installation in
 271                   ``$APEX_HOME/examples/scripts/pcvs/vpnsla``.
 272
 273                .. container:: sect2
 274
 275                   .. rubric:: Start all Software
 276                      :name: start_all_software
 277
 278                   .. container:: paragraph
 279
 280                      Create environment variables in a file, say
 281                      ``env.sh``. In each new Xterm
 282
 283                   .. container:: ulist
 284
 285                      -  Source these environment settings, e.g.
 286                         ``. ./env.sh``
 287
 288                      -  Run the commands below as root (``sudo`` per
 289                         command or ``sudo -i`` for interactive mode as
 290                         shown below)
 291
 292                   .. container:: listingblock
 293
 294                      .. container:: content
 295
 296                         ::
 297
 298                            #!/usr/bin/env bash
 299
 300                            export src_dir=/usr/local/src
 301                            export APEX_HOME=/opt/ericsson/apex/apex
 302                            export APEX_USER=apexuser
 303
 304                   .. container:: paragraph
 305
 306                      In a new Xterm, start Floodlight
 307
 308                   .. container:: listingblock
 309
 310                      .. container:: content
 311
 312                         ::
 313
 314                            sudo -i
 315                            . ./env.sh
 316                            cd $src_dir/floodlight-master && java -jar target/floodlight.jar
 317
 318                   .. container:: paragraph
 319
 320                      In a new Xterm start Mininet
 321
 322                   .. container:: listingblock
 323
 324                      .. container:: content
 325
 326                         ::
 327
 328                            sudo -i
 329                            . ./env.sh
 330                            mn -c && python $APEX_HOME/examples/scripts/pcvs/vpnsla/MininetTopology.py
 331
 332                   .. container:: paragraph
 333
 334                      In a new Xterm, start Kafka
 335
 336                   .. container:: listingblock
 337
 338                      .. container:: content
 339
 340                         ::
 341
 342                            sudo -i
 343                            . ./env.sh
 344                            /opt/Kafka/kafka_2.12-1.0.0/bin/kafka-server-start.sh /opt/Kafka/kafka_2.12-1.0.0/config/server.properties
 345
 346                   .. container:: paragraph
 347
 348                      In a new Xerm start APEX with the Kafka
 349                      configuration for this demo
 350
 351                   .. container:: listingblock
 352
 353                      .. container:: content
 354
 355                         ::
 356
 357                            cd $APEX_HOME
 358                            ./bin/apexApps.sh engine -c examples/config/pcvs/vpnsla/kafka2kafka.json
 359
 360                   .. container:: paragraph
 361
 362                      In a new Xterm start the Link Monitor. The Link
 363                      Monitor has a 30 second sleep to slow down the
 364                      demonstration. So the first action of it comes 30
 365                      seconds after start. Every new action in 30 second
 366                      intervals.
 367
 368                   .. container:: listingblock
 369
 370                      .. container:: content
 371
 372                         ::
 373
 374                            sudo -i
 375                            . ./env.sh
 376                            cd $src_dir
 377                            xterm -hold -e 'python3 $src_dir/kafka-python/LinkMonitor.py' &
 378
 379                   .. container:: paragraph
 380
 381                      Now all software should be started and the demo is
 382                      running. The Link Monitor will send link up events,
 383                      picked up by APEX which triggers the policy. Since
 384                      there is no problem, the policy will do nothing.
 385
 386                .. container:: sect2
 387
 388                   .. rubric:: Create 2 Video Streams with VLC
 389                      :name: create_2_video_streams_with_vlc
 390
 391                   .. container:: paragraph
 392
 393                      In the Mininet console, type ``xterm A1 A2`` and
 394                      ``xterm B1 B2`` to open terminals on these nodes.
 395
 396                   .. container:: paragraph
 397
 398                      ``A2`` and ``B2`` are the receiving nodes. In these
 399                      terminals, run ``vlc-wrapper``. In each opened VLC
 400                      window do
 401
 402                   .. container:: ulist
 403
 404                      -  Click Media → Open Network Stream
 405
 406                      -  Give the URL as ``rtp://@:5004``
 407
 408                   .. container:: paragraph
 409
 410                      ``A1`` and ``B1`` are the sending nodes (sending
 411                      the video stream) In these terminals, run
 412                      ``vlc-wrapper``. In each opened VLC window do
 413
 414                   .. container:: ulist
 415
 416                      -  Click Media → Stream
 417
 418                      -  Add the video (from ``/usr/local/src/videos``)
 419
 420                      -  Click ``Stream``
 421
 422                      -  Click ``Next``
 423
 424                      -  Change the destination
 425                         ``RTP / MPEG Transport Stream`` and click
 426                         ``Add``
 427
 428                      -  Change the address and type to ``10.0.0.2`` in
 429                         ``A1`` and to ``10.0.0.4`` in ``B1``
 430
 431                      -  Turn off ``Active Transcoding`` (this is
 432                         important to minimize CPU load)
 433
 434                      -  Click ``Next``
 435
 436                      -  Click ``Stream``
 437
 438                   .. container:: paragraph
 439
 440                      The video should be streaming across the network
 441                      from ``A1`` to ``A2`` and from ``B1`` to ``B2``. If
 442                      the video streams a slow or interrupted the CPU
 443                      load is too high. In these cases either try a
 444                      better machine or use a different (lower quality)
 445                      video stream.
 446
 447                .. container:: sect2
 448
 449                   .. rubric:: Take out L09 and let the Policy do it’s
 450                      Magic
 451                      :name: take_out_l09_and_let_the_policy_do_it_s_magic
 452
 453                   .. container:: paragraph
 454
 455                      Now it is time to take out the link ``L09``. This
 456                      will be picked up by the Link Monitor, which sends
 457                      a new event (L09 DOWN) to the policy. The policy
 458                      then will calculate which customer should be
 459                      impeded (throttled). This will continue, until SLAs
 460                      are violated, then a priority calculation will kick
 461                      in (Customer ``A`` is prioritized in the setup).
 462
 463                   .. container:: paragraph
 464
 465                      To initiate this, simply type ``link s5 s6 down``
 466                      in the Mininet console followed by ``exit``.
 467
 468                   .. container:: paragraph
 469
 470                      If you have the video streams running, you will see
 471                      one or the other struggeling, depending on the
 472                      policy decision.
 473
 474                .. container:: sect2
 475
 476                   .. rubric:: Reset the Demo
 477                      :name: reset_the_demo
 478
 479                   .. container:: paragraph
 480
 481                      If you want to reset the demo, simple stop (in this
 482                      order) the following process
 483
 484                   .. container:: ulist
 485
 486                      -  Link Monitor
 487
 488                      -  APEX
 489
 490                      -  Mininet
 491
 492                      -  Floodlight
 493
 494                   .. container:: paragraph
 495
 496                      Then restart them in this order
 497
 498                   .. container:: ulist
 499
 500                      -  Floodlight
 501
 502                      -  Mininet
 503
 504                      -  APEX
 505
 506                      -  Link Monitor
 507
 508                .. container:: sect2
 509
 510                   .. rubric:: Monitor the Demo
 511                      :name: monitor_the_demo
 512
 513                   .. container:: paragraph
 514
 515                      Floodlight and APEX provide REST interfaces for
 516                      monitoring.
 517
 518                   .. container:: ulist
 519
 520                      -  Floodlight: see `Floodlight
 521                         Docs <https://floodlight.atlassian.net/wiki/spaces/floodlightcontroller/pages/40403023/Web+GUI>`__
 522                         for details on how to access the monitoring. In
 523                         a standard installation as we use here, pointing
 524                         browser to the URL
 525                         ``http://localhost:8080/ui/pages/index.html``
 526                         should work on the same host
 527
 528                      -  APEX please see the APEX documentation for
 529                         `Monitoring
 530                         Client <https://ericsson.github.io/apex-docs/user-manual/engine-apps/um-engapps-eng-monitoring.html>`__
 531                         or `Full
 532                         Client <https://ericsson.github.io/apex-docs/user-manual/engine-apps/um-engapps-full-client.html>`__
 533                         for details on how to monitor APEX.
 534
 535
 536 VPN SLA Policy
 537 ^^^^^^^^^^^^^^
 538
 539             .. container:: sectionbody
 540
 541                .. container:: paragraph
 542
 543                   The VPN SLA policy is designed as a MEDA policy. The
 544                   first state (M = Match) takes the trigger event (a
 545                   link up or down) and checks if this is a change to the
 546                   known topology. The second state (E = Establish) takes
 547                   all available information (trigger event, local
 548                   context) and defines what situation we have. The third
 549                   state (D = Decide) takes the situation and selects
 550                   which algorithm is best to process it. This state can
 551                   select between ``none`` (nothing to do), ``solved`` (a
 552                   problem is solved now), ``sla`` (compare the current
 553                   customer SLA situation and select one to impede), and
 554                   ``priority`` (impede non-priority customers). The
 555                   fourth and final state (A = Act) selects the right
 556                   action for the taken decision and creates the response
 557                   event sent to the orchestrator.
 558
 559                .. container:: paragraph
 560
 561                   We have added three more policies to set the local
 562                   context: one for adding nodes, one for adding edges
 563                   (links), and one for adding customers. These policies
 564                   do not realize any action, they are only here for
 565                   updating the local context. This mechanism is the
 566                   fasted way to update local context, and it is
 567                   independent of any context plugin.
 568
 569                .. container:: paragraph
 570
 571                   The policy uses data defined in Avro, so we have a
 572                   number of Avro schema definitions.
 573
 574 Context Schemas
 575 ---------------
 576
 577          .. container:: sect1
 578
 579             .. container:: sectionbody
 580
 581                .. container:: paragraph
 582
 583                   The context schemas are for the local context. We
 584                   model edges and nodes for the topology, customers, and
 585                   problems with all information on detected problems.
 586
 587                   .. container:: ulist
 588
 589                      -  |avroSchemaEdges_link|
 590                      -  |avroSchemaNodes_link|
 591                      -  |avroSchemaCustomers_link|
 592
 593
 594 Trigger Schemas
 595 ---------------
 596
 597         .. container:: sect1
 598
 599             .. container:: sectionbody
 600
 601                .. container:: paragraph
 602
 603                   The trigger event provides a status as ``UP`` or
 604                   ``DOWN``. To avoid tests for these strings in the
 605                   logic, we defined an Avro schema for an enumeration (|avroSchemaLinkStatus_link|).
 606                   This does not impact the trigger system (it can still
 607                   send the strings), but makes the task logic simpler.
 608
 609
 610
 611 Context Logic Nodes
 612 --------------------
 613
 614          .. container:: sect1
 615
 616             .. container:: sectionbody
 617
 618                .. container:: paragraph
 619
 620                   The node context logic simply takes the trigger event
 621                   (for context) and creates a new node in the local
 622                   context topology (|cntxtNodes_link|).
 623
 624 Context Logic Edges
 625 --------------------
 626
 627          .. container:: sect1
 628
 629             .. container:: sectionbody
 630
 631                .. container:: paragraph
 632
 633                   The edge context logic simply takes the trigger event
 634                   (for context) and creates a new edge in the local
 635                   context topology (|cntxtEdges_link|).
 636
 637
 638 Context Logic Customer
 639 ----------------------
 640
 641          .. container:: sect1
 642
 643             .. container:: sectionbody
 644
 645                .. container:: paragraph
 646
 647                   The customer context logic simply takes the trigger
 648                   event (for context) and creates a new customer in the
 649                   local context topology (|cntxtCustomer_link|).
 650
 651
 652 Logic: Match
 653 ------------
 654
 655          .. container:: sect1
 656
 657             .. container:: sectionbody
 658
 659                .. container:: paragraph
 660
 661                   This is the logic for the match state. It is kept very
 662                   simple. Beside taking the trigger event, it also
 663                   creates a timestamp. This timestamp is later used for
 664                   SLA and downtime calculations as well as for some
 665                   performance information of the policy .
 666                   Sample |taskMatch_link|
 667
 668
 669 Logic: Policy Establish State
 670 -----------------------------
 671
 672          .. container:: sect1
 673
 674             .. container:: sectionbody
 675
 676                .. container:: paragraph
 677
 678                   This is the logic for the establish state. It is the
 679                   most complicated logic, since establishing a situation
 680                   for a decision is the most important part of any
 681                   policy. First, the policy describes what we find (the
 682                   switch block), in terms of 8 normal situations and 1
 683                   extreme error case.
 684
 685                .. container:: paragraph
 686
 687                   If required, it creates local context information for
 688                   the problem (if it is new) or updates it (if the
 689                   problem still exists). It also calculates customer SLA
 690                   downtime and checks for any SLA violations. Finally,
 691                   it creates a situation object.
 692                   Sample |taskEstablish_link|
 693
 694 Logic: Policy Decide State
 695 --------------------------
 696
 697          .. container:: sect1
 698
 699             .. container:: sectionbody
 700
 701                .. container:: paragraph
 702
 703                   The decide state can select between different
 704                   algorithms depending on the situation. So it needs a
 705                   Task Selection Logic (TSL). This TSL select a task in
 706                   the current policy execution (i.e. potentially a
 707                   different one per execution).
 708                   Sample |tslDecide_Link|
 709
 710                .. container:: paragraph
 711
 712                   The actual task logic are then ``none``, ``solved``,
 713                   ``sla``, and ``priority``.
 714                   Sample task logic are as given below :
 715
 716                   .. container:: ulist
 717
 718                      -  |taskDecideNone_link|
 719                      -  |taskDecideSolved_Link|
 720                      -  |taskDecideSla_link|
 721                      -  |taskDecidePriority_Link|
 722
 723
 724 Logic: Policy Act State
 725 ------------------------
 726
 727          .. container:: sect1
 728
 729             .. container:: sectionbody
 730
 731                .. container:: paragraph
 732
 733                   This is the logic for the act state. It is simply
 734                   selecting an action, and creating the repsonse event
 735                   for the orchestrator (the output of the policy).
 736                   Sample |taskAct_link|
 737
 738 CLI Spec
 739 --------
 740
 741          .. container:: sect1
 742
 743             .. rubric:: Complete Policy Definition
 744                :name: complete_policy_definition
 745
 746             .. container:: sectionbody
 747
 748                .. container:: paragraph
 749
 750                   The complete policy definition is realized using the
 751                   APEX CLI Editor. The script below shows the actual
 752                   policy specification. All logic and schemas are
 753                   included (as macro file).
 754                   Sample |vpnsla-apex_link|
 755
 756
 757 Context Events Nodes
 758 --------------------
 759
 760          .. container:: sect1
 761
 762             .. container:: sectionbody
 763
 764                .. container:: paragraph
 765
 766                   The following events create all nodes of the topology.
 767
 768                   .. container:: ulist
 769
 770                      -  |ctxtNodesJson_link|
 771
 772
 773 Context Events Edges
 774 --------------------
 775
 776          .. container:: sect1
 777
 778             .. container:: sectionbody
 779
 780                .. container:: paragraph
 781
 782                   The following events create all edges of the topology.
 783
 784                   .. container:: ulist
 785
 786                      -  |ctxtEdgesJson_link|
 787
 788
 789 Context Events Customers
 790 ------------------------
 791
 792          .. container:: sect1
 793
 794             .. container:: sectionbody
 795
 796                .. container:: paragraph
 797
 798                   The following events create all customers of the topology.
 799
 800                   .. container:: ulist
 801
 802                      -  |ctxtCustomerJson_link|
 803
 804
 805 Trigger Examples
 806 ----------------
 807
 808          .. container:: sect1
 809
 810             .. container:: sectionbody
 811
 812                .. container:: paragraph
 813
 814                   The following events are examples for trigger events
 815
 816                   .. container:: ulist
 817
 818                      -  |triggerEdgeJson_link|
 819
 820 Link Monitor
 821 ------------
 822
 823          .. container:: sect1
 824
 825             .. container:: sectionbody
 826
 827                .. container:: paragraph
 828
 829                   The Link Monitor is a Python script. At startup, it
 830                   sends the context events to APEX to initialize the
 831                   topology and the customers. Then it takes events from
 832                   Kafka and sends them to APEX.
 833                   Sample |linkMonitor_link|
 834
 835 Mininet Topology
 836 ----------------
 837
 838          .. container:: sect1
 839
 840             .. container:: sectionbody
 841
 842                .. container:: paragraph
 843
 844                   The topology is realized using Mininet. This
 845                   script is used to establish the topology and to realize
 846                   network configurations.
 847                   Sample |mininetTopology_link|
 848
 849
 850    .. container::
 851       :name: footer-text
 852
 853       2.3.0-SNAPSHOT
 854       Last updated 2020-04-03 16:04:24 IST
 855
 856
 857 .. |ONAP| image:: ../../../images/logos.png
 858    :class: builtBy
 859    :target: http://www.onap.org/
 860
 861 .. |VPN SLA Architecture| image:: images/pcvs/vpnsla-arch.png
 862
 863 .. |avroSchemaEdges_link| raw:: html
 864
 865   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/avro/topology-edges.avsc" target="_blank">AVRO Schema Edges</a>
 866 .. |avroSchemaNodes_link| raw:: html
 867
 868   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src//main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/avro/topology-nodes.avsc" target="_blank">AVRO Schema Nodes</a>
 869 .. |avroSchemaCustomers_link| raw:: html
 870
 871   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/avro/customers.avsc" target="_blank">AVRO Schema Customers</a>
 872 .. |avroSchemaLinkStatus_link| raw:: html
 873
 874   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/avro/link-status.avsc" target="_blank">AVRO Schema Link Status</a>
 875 .. |cntxtNodes_link| raw:: html
 876
 877   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/logic/ctxt-nodes.js" target="_blank">Logic Node Context</a>
 878 .. |cntxtEdges_link| raw:: html
 879
 880   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/logic/ctxt-edges.js" target="_blank">Logic Edge Context</a>
 881 .. |cntxtCustomer_link| raw:: html
 882
 883   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/logic/ctxt-customer.js" target="_blank">Logic Customer Context</a>
 884 .. |taskMatch_link| raw:: html
 885
 886   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/logic/task-match.js" target="_blank">Logic Policy Match State</a>
 887 .. |taskEstablish_link| raw:: html
 888
 889   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/logic/task-establish.js" target="_blank">Logic Policy Establish State</a>
 890 .. |tslDecide_Link| raw:: html
 891
 892   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/logic/tsl-decide.js" target="_blank">JS Logic Policy Decide State - TSL</a>
 893 .. |taskDecideNone_link| raw:: html
 894
 895   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/logic/task-decide-none.js" target="_blank">Logic: Decide None</a>
 896 .. |taskDecideSolved_Link| raw:: html
 897
 898   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/logic/task-decide-solved.js" target="_blank">Logic: Decide Solved</a>
 899 .. |taskDecideSla_link| raw:: html
 900
 901   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/logic/task-decide-sla.js" target="_blank">Logic: Decide SLA</a>
 902 .. |taskDecidePriority_Link| raw:: html
 903
 904   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/logic/task-decide-priority.js" target="_blank">Logic: Decide Priority</a>
 905 .. |taskAct_link| raw:: html
 906
 907   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/logic/task-act.js" target="_blank">Logic Policy Act State</a>
 908 .. |vpnsla-apex_link| raw:: html
 909
 910   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/org/onap/policy/apex/examples/pcvs/vpnsla/vpnsla.apex" target="_blank">APEX VPN SLA Policy Specification</a>
 911 .. |ctxtNodesJson_link| raw:: html
 912
 913   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/examples/events/pcvs/vpnsla/CtxtNodes.json" target="_blank">Context Events Nodes</a>
 914 .. |ctxtEdgesJson_link| raw:: html
 915
 916   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/examples/events/pcvs/vpnsla/CtxtEdges.json" target="_blank">Context Events Edges</a>
 917 .. |ctxtCustomerJson_link| raw:: html
 918
 919   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/examples/events/pcvs/vpnsla/CtxtCustomers.json" target="_blank">Context Events Customers</a>
 920 .. |triggerEdgeJson_link| raw:: html
 921
 922   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/examples/events/pcvs/vpnsla/Trigger_Edge09.json" target="_blank">Trigger Examples</a>
 923 .. |linkMonitor_link| raw:: html
 924
 925   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/examples/scripts/pcvs/vpnsla/LinkMonitor.py" target="_blank">Link Monitor</a>
 926 .. |mininetTopology_link| raw:: html
 927
 928   <a href="https://github.com/onap/policy-apex-pdp/tree/master/examples/examples-pcvs/src/main/resources/examples/scripts/pcvs/vpnsla/MininetTopology.py" target="_blank">Mininet Topology</a>